Serum Free Radical Scavenging Capacity Profiles of Patients with Chronic Obstructive Pulmonary Disease

Figures & data

Table 1 Measurement Conditions of Each Free Radical Scavenging Capacity

Free Radical	Precursor	Lighting Conditions	Illumination Period	Spin Trap
^•OH	H2O2	UV light	5s	CYPMPO
O2^−•	Riboflavin	Visible light	30s	CYPMPO
RO^•	AAPH	UV light	5s	CYPMPO
ROO^•	t-butyl hydroperoxide	UV light	5s	CYPMPO
^•CH3	H2O2, DMSO	UV light	5s	CYPMPO
^1O2	Rosebengal	Visible light	60s	4-OH-TEMP

Notes:^•OH, hydroxyl radical; O₂^−•, superoxide radical; RO^•, alkoxyl radical; ROO^•, alkylperoxyl radical; ^•CH₃, methyl radical; ¹O₂, Singlet oxygen; AAPH, 2,2ʹ-azobis (2-amidinopropane) hydrochloride; DMSO, dimethyl sulfoxide; CYPMPO, 5-(2,2-dimethyl-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide; 4-OH-TEMP, 4-hydroxy-2,2,6,6-tetra-methylpiperidine.

Table 2 Patients Characteristics

Number	37
Male / Female	35/2
Age, yo	70.9±8.9
Smoking history, pack-years	68.5±29.6
Current/Ex-smokers, n(%)	12(32)/25(68)
mMRC	2.2±1.0
BMI, kg/m^2	20.5±3.2
GOLD stage, n
I	5
II	17
III	9
IV	6
VC %pred.	100.6±20.5
FEV1%pred.	55.2±21.5
RV %pred.	138.7±39.1
DLco %pred.	43.6±21.9
Blood eosinophil counts, /μL	176.5±103.8
Blood eosinophil, %	2.9±1.4
IgE, IU/mL	290.6±357.0

Note: Values are mean±SD.

Abbreviations: mMRC, the modified Medical Research Council scale; BMI, body mass index; GOLD, Global Initiative for Chronic Obstructive Lung Disease; VC, vital capacity; FEV₁, forced expiratory volume in 1 second; RV, residual volume; DLco, diffusing capacity for carbon monoxide.

Table 3 Free Radical Scavenging Capacity and Severity of COPD

	Control	COPD	COPD
			I	II	III	IV
Number	8	37	5	17	9	6
^•OH, mM	20.8±14.0	11.9±7.3*	13.1±1.9	11.5±10.0	12.5±3.0	11.8±5.7
O2^−•, U/mL	1.85±0.63	1.58±0.77	2.18±1.59	1.44±0.54	1.42±0.35	1.74±0.80
RO^•, mM	1.34±0.38	1.33±0.41	1.41±0.31	1.23±0.38	1.36±0.53	1.51±0.38
ROO^•, mM	1.11±0.41	1.48±0.51	1.32±0.39	1.53±0.70	1.52±0.26	1.41±0.25
^•CH3, µM	2.71±2.95	1.82±2.27	1.15±0.61	2.31±2.72	1.27±1.12	1.73±2.91
^1O2, mM	22.4±15.6	22.3±12.3	17.4±12.4	19.7±10.3	29.8±14.3	21.1±12.0

Notes: Values are mean ± SD. *p < 0.05 vs control. Severity of COPD is according to GOLD classification.

Abbreviations: ^•OH, hydroxyl radical; O₂^−•, superoxide radical; RO^•, alkoxyl radical; ROO^•, alkylperoxyl radical; ^•CH₃, methyl radical; ¹O₂, Singlet oxygen.

Figure 1 A radar chart illustration of the relative scavenging capacity data listed in Table 1. Percent changes in the capacity of COPD patients are shown in each free radical species. *p < 0.05 vs control subjects.

Abbreviations: ^・OH, hydroxyl radical; O₂^−・, superoxide radical; RO^・, alkoxyl radical; ROO^・, alkylperoxyl radical; ^・CH₃, methyl radical; ¹O₂, Singlet oxygen.

Table 4 Relationship Between Free Radical Scavenging Capacity and Goddard Classification

	Goddard Classification			p value
	Mild	Moderate	Severe
Number	24	8	5
^•OH, mM	9.39±3.07	10.78±2.45	13.19±9.11	0.4781
O2^−•, U/mL	1.34±0.41	1.73±1.35	1.60±0.58	0.6552
RO^•, mM	1.21±0.46	1.06±0.41	1.46±0.36*	0.0401
ROO^•, mM	1.49±0.70	1.31±0.42	1.54±0.50	0.5537
^•CH3, µM	1.60±0.69	2.36±2.40	1.69±2.53	0.7593
^1O2, mM	21.0±11.2	17.5±11.7	24.2±12.8	0.4530

Notes: Values are mean ± SD. *p<0.02 vs moderate group.

Abbreviations: ^•OH, hydroxyl radical; O₂^−•, superoxide radical; RO^•, alkoxyl radical; ROO^•, alkylperoxyl radical; ^•CH₃, methyl radical; ¹O₂, Singlet oxygen.

Table 5 Relationship Between Free Radical Scavenging Capacity and Exacerbation Frequency

	Exacerbation Frequency			p value
	0	1	≥2
Number	24	8	5
^•OH, mM	12.6±8.5	11.6±5.2	9.79±4.0	0.7503
O2^−•, U/mL	1.51±0.87	1.71±0.66	1.75±0.40	0.7173
RO^•, mM	1.27±0.32^#	1.68±0.34	1.09±0.62*	0.0129
ROO^•, mM	1.51±0.57	1.38±0.26	1.48±0.57	0.8283
^•CH3, µM	1.50±1.58	1.54±2.54	3.76±3.82	0.1194
^1O2, mM	21.5±12.8	21.8±11.9	27.9±11.0	0.6382

Notes: Values are mean ± SD. *p < 0.01, ^#p<0.05 vs one exacerbation for one year after enrollment.

Abbreviations: ^•OH, hydroxyl radical; O₂^−•, superoxide radical; RO^•, alkoxyl radical; ROO^•, alkylperoxyl radical; ^•CH₃, methyl radical; ¹O₂, Singlet oxygen.

Figure 2 A radar chart illustration of the relative scavenging capacity. Percent changes in the capacity of COPD patients are shown in each free radical species. (a) Survived patients with COPD, (b) Deceased patients with COPD. *p < 0.05 vs control, ^#p<0.05 vs survived patients with COPD.

Abbreviations:^・OH, hydroxyl radical; O₂^−・, superoxide radical; RO^・, alkoxyl radical; ROO^・, alkylperoxyl radical; ^・CH₃, methyl radical; ¹O₂, Singlet oxygen.